TEMPORAL PATTERNS OF ANTIHYPERTENSIVE MEDICATION USE AMONG ELDERLY PATIENTS - THE CARDIOVASCULAR HEALTH STUDY

Objectives.-To estimate the incidence of newly treated hypertension an d to describe the patterns of antihypertensive medication use among th ose aged 65 years and older. Design.-Medicare eligibility lists from f our US communities (Forsyth County, North Carolina; Washington County, Maryland; Sacramento County, California; and Pittsburgh, Pa) were use d to obtain a representative sample of 5201 community-dwelling elderly for the Cardiovascular Health Study, a prospective cohort study of ri sk factors for coronary heart disease and stroke. Participants were ex amined at baseline and again 1 year later. The two examinations includ ed standardized questionnaires, blood pressure measurements, and the a ssessment of medication use by medication inventory. In this cohort an alysis, we excluded 231 subjects (4.4%) who did not return for follow- up, 69 (1.3%) who had missing data for medications, and another 495 (9 .5%) who were taking ''antihypertensive'' medications for an indicatio n other than high blood pressure. Interventions.-None. Results.-Among the 4406 participants, 1613 used antihypertensive medications at both visits. Between the two visits, 144 started and 115 stopped antihypert ensive therapy. Among nonusers at baseline, the annual incidence of ne wly treated hypertension was 5.2% in women and 5.6% in men. Due to the number of participants who stopped therapy, the overall prevalence of antihypertensive treatment increased only slightly, from 40.7% to 41. 1% in women and from 37.1% to 38.2% in men, during 1 year of follow-up . After adjustment for age, systolic blood pressure, number of antihyp ertensive drugs, diabetes, and cardiovascular disease, the newly treat ed hypertensives were about half as likely as the previously treated h ypertensives to receive diuretics (odds ratio [OR], 0.59; P=.008) or b eta-blockers (OR, 0.52; P=.01); and they were about twice as likely to receive calcium channel blockers (OR, 1.88; P<.004) or angiotensin co nverting enzyme inhibitors (OR, 2.40; P<.001). A similar pattern of wi thin-person changes over time was apparent among the continuous users. Conclusions.-Between June 1990 and June 1991, physicians were increas ingly prescribing angiotensin converting enzyme inhibitors and calcium channel blockers in place of diuretics and beta-blockers for the trea tment of hypertension in elderly patients, especially for those just s tarting therapy.